tools: ynl: add a sample for TC

Add a very simple TC dump sample with decoding of fq_codel attrs:

  # ./tools/net/ynl/samples/tc
        dummy0: fq_codel  limit: 10240p target: 5ms new_flow_cnt: 0

proving that selector passing (for stats) works.

Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250520161916.413298-13-kuba@kernel.org


Signed-off-by: Jakub Kicinski <kuba@kernel.org>